1. Field
This application relates generally to the removal of excess material from a contoured surface, and may relate, more specifically to the removal of excess low-observable performance filler paste (LO filler) from over fastener holes in a composite aircraft skin panel.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
Low-observable performance material (LO filler) is applied as a filler paste over each of approximately 20,000 exterior fasteners on the F-35 aircraft. The application often leaves about 0.010″-0.020″ of LO filler proud of the surface. To achieve desired low-observable characteristics it's desirable to remove enough of the excess LO filler so that an outer surface of remaining LO filler lies nearly flush with an outer surface of the skin panel (0.002-0.005″ proud, depending on working surface contour curvature). Known methods of removing the excess LO filler include use of random orbital sanders, rough file, razor blades, and/or other manually driven hand tools. These methods have proven very time-consuming and exhausting and, when used without caution or skill, can result in damage to the composite skin surface surrounding the fasteners.